1.synchronized+wait()+notify()方式

static Object object = new Object();
    public static void main(String[] args) {
        char[] num = "1234567".toCharArray();
        char[] str = "ABCDEFG".toCharArray();
        new Thread(() -> {
            synchronized (object) {
                for (char c : str) {
                    
 
try {
                        System.out.println(Thread.currentThread().getName()+" = " + c);
                        object.wait();
                        object.notify();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }

        }, 
 
"t1").start();
        new Thread(() -> {
            synchronized (object) {
                for (char c : num) {
                    try {
                        System.out.println(Thread.currentThread().getName()+" = " + c);
                        object.notify();
                        object.wait();

                    } 
 
catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }

        }, "t2").start();

2.Lock+Condition 、await()+signal()

static Lock lock = new ReentrantLock();
    static Condition condition = lock.newCondition();
    public static void main(String[] args) {
        char[] num = "1234567".toCharArray();
        char[] str = "ABCDEFG".toCharArray();
        new Thread(()->{
            lock.lock();
            try {
                for (char c : str) {
                    System.out.println(Thread.currentThread().getName()+" = " + c);
                    condition.await();
                    condition.signal();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                lock.unlock();
            }
        },"t1").start();
        new Thread(()->{
            lock.lock();
            try {
                for (char c : num) {
                    System.out.println(Thread.currentThread().getName()+" = " + c);
                    condition.signal();
                    condition.await();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                lock.unlock();
            }
        },"t2").start();
    }

3.AtomicInteger原子類

static AtomicInteger thredNo=new AtomicInteger(1);
    public static void main (String[] args){
        char[] num="1234567".toCharArray();
        char[] str="ABCDEFG".toCharArray();


        new Thread(()->{
            for (char c : num) {
                //如果不是1就一直返回空，直到執行列印，列印完之後把原子物件變成2
                while (thredNo.get()!=1){}
                System.out.println(c);
                thredNo.set(2);
            }

        },"t1").start();


        new Thread(()->{
            for (char c : str) {
                //如果不是2就一直返回空，直到執行列印，列印完之後把原子物件變成1
                while (thredNo.get()!=2){}
                System.out.println(c);
                thredNo.set(1);
            }

        },"t1").start();
    }

4.LockSupport

static Thread t1 ;
    static Thread t2 ;
    public static void main(String[] args) {
        char[] num = "1234567".toCharArray();
        char[] str = "ABCDEFG".toCharArray();
        t1 = new Thread(()->{
            for (char c : num) {
                System.out.println(Thread.currentThread().getName()+"::::"+c);
                java.util.concurrent.locks.LockSupport.unpark(t2);
                java.util.concurrent.locks.LockSupport.park();
            }
        },"t1");
        t2 = new Thread(()->{
            for (char c : str) {
                java.util.concurrent.locks.LockSupport.park();
                System.out.println(Thread.currentThread().getName()+"::::"+c);
                java.util.concurrent.locks.LockSupport.unpark(t1);
            }
        },"t2");
        t1.start();
        t2.start();
    }